Hi Dattatray, thanks for your question.
CPU Load is a measure of the active process queue for the CPU. It is a metric pulled directly off of the host OS, meaning that the OS is what reports the CPU Load to Dynatrace. As far as I know, only our *nix agent can get CPU Load, as Windows does not compute this metric. CPU Load is more of a metric of how much processing has to happen subsequently, rather than the active amount of processing happening at a given time.
Please see this article for more in-depth specifications of how CPU Load is calculated.